I'm wondering what types of devices exist that can detect how close someone is to falling asleep. I have heard of several devices that may be able to do this, but I haven't been able to find very solid information.
- EEG: I assume these could detect falling asleep quite effectively; though, I'd like to know if there are any other devices that would work as well.
- EKG/ECG: I found this paper that claims you can use a Lorenz plot to detect correlation between heartrate and falling asleep.
- GSR: A lot of people say a GSR can be used, but I have yet to find any papers/data that describe the correlation between GSR and falling asleep
- Pulse Oximeter: someone mentioned to me that these work as well, though I haven't been able to find much information